Explanation on page 4-4, carb section of the manual
I decided to just block the enricher in the "warm engine" position. If you look at the diagram on 4-4 of the manual - I removed the return spring that pushes the enricher plungers out. I then bent a piece of aluminum sheet in a "V" shape and wedged it on top of the cam to hold the plungers in.
As I said, I don't know how this thing even ran. The pilot jet was totally plugged and the pilot screw was full of crap. Float bowl coated with varnish. I think it was idling on the enricher circuit alone (which was stuck in the "cold start" position). The pilot screw was opened about 4 turns, book says 1 3/4. Since I will now be without a choke, I opened it another 1/2 turn to 2 1/4.
The old air filter is deteriorated so I have a new one coming. I installed the carb, pulled a vacuum on the petcock line to get the float bowl full, and then - she started right up, even better than before! And that was without the airbox/filter installed, so it will actually have more restriction = run richer. I didn't run it too long without the filter on but she seemed to rev out OK too.
I'll update when I get the filter and take it for a proper test ride. May be a bear to start in cold weather, but I'll take it for now.